9 replies to this topic

[ads7]

Prepping the Moo for sale and want to get her running sweetly again after a recent bogging down / cutting out issue..

The car had been hesitant at low rpm for a few weeks, planting my foot on the throttle and keeping the revs up worked.

Then on a recent long run she got really low of fuel and as soon as I brimmed to tank full the problem completely disappeared and she ran perfectly. I'd guess muck in the fuel tank?

Then she stalled and wouldn't run under load so recovery truck home. I opened up the float chamber and found crud in the bottom so cleaned that out, together with the jet - I did notice that the non adjustable plastic float gap between the chamber top is approx 1/4" when it should be 1/8"??

Seems like the car is stalling as soon as the float chamber is full.

Think perhaps I've got two issues here. I need a new float and also I need to drain the tank which is half full to ensure any muck is eliminated.

Any ideas?

[detroitmini]

Hey ads7,

 

I see its almost been two months but I am looking into the same thing, only with opposite thinking. My Mini constantly ran rich no matter how high I raised the jet. While taking the carb apart, I noticed 5/32" between float chamber top and float when flipped upside down. I read that SU recommends anywhere from 1/8" to 7/16". Here is a guide to what they recommend:  

 

http://sucarb.co.uk/...ng-float-height

Edited by detroitmini, 31 March 2022 - 11:59 PM.

[coopertaz]

if gap is too high carb will empty and car stalls, too small carb can overflow. never had float gap affect mixture, are needle and jet straight and is piton free to move in housing and fully seating on bridge when lowered?

Edited by coopertaz, 01 April 2022 - 01:40 PM.

[ads7]

Problem solved. Muck in the piston chamber. Cleaned and runs perfectly 👍

[cal844]

Problem solved. Muck in the piston chamber. Cleaned and runs perfectly 👍

Fit a fuel filter

[nicklouse]

if gap is too high carb will empty and car stalls, too small carb can overflow. never had float gap affect mixture, are needle and jet straight and is piton free to move in housing and fully seating on bridge when lowered?

The float only controls fuel into the float. Ie when full it closes the flow. Crap can stop the valve closing leading to overflow. If you are running out of fuel then it is a pump issue. 

[ads7]

Problem solved. Muck in the piston chamber. Cleaned and runs perfectly 👍

Fit a fuel filter

Done 👍

[ac427]

Does this happen if the fuel left in the carb and the Mini is left to stand for a few years?

Is there a gasket that will need replacing after the float chamber has been opened?

Edited by ac427, 11 April 2022 - 07:59 AM.

[gazza82]

Does this happen if the fuel left in the carb and the Mini is left to stand for a few years?

If has ethanol in it, it doesn't take years ..

Is there a gasket that will need replacing after the float chamber has been opened?

There is one under the float chamber cover, but if you're careful you can re-use it.

[coopertaz]

 

if gap is too high carb will empty and car stalls, too small carb can overflow. never had float gap affect mixture, are needle and jet straight and is piton free to move in housing and fully seating on bridge when lowered?

The float only controls fuel into the float. Ie when full it closes the flow. Crap can stop the valve closing leading to overflow. If you are running out of fuel then it is a pump issue. 

 

had gap too large once to try to solve overflowing carb (new to minis at this stage years ago) and when on full load car would eventually die, just speaking from own experience.